So there I was in the bar, having a pint and a cigarette and loudly relating a hilarious story about another comic's sexual proclivities, in particular their fondness for having reviews read to them as foreplay, when I was accosted by two of my fans. How lovely, you might think – except these fans were aged six and eight.

I'm a presenter on Children's BBC, you see. And it's easy to forget, as an adult, the wide-eyed wonder kids have for anyone on telly. The two little girls wanted a photograph with the "nice lady off the TV" – not a bedraggled, foul-mouthed tramp hanging off a bar.

In 2010, lots of people brought their children to my show because I looked cute on my poster. I'm not cute, though. I'm awful. Just because I'm the same height as a child doesn't mean I do jokes about Justin Bieber. But even I don't want to see dreams die in the eyes of a child.

The problem is that CBBC shows like Horrible Histories have made comedy for kids cool. But mistaking my standup show for something that's suitable for children is like mistaking a paper shredder for a Dyson Airblade. Kids, keep clear – I will take your fingers off! There should be a symbol you can put on posters, a crossed-out child perhaps – for my good as much as theirs.

I stood beside the eight-year-old (who dwarfed me) and tried not to breathe lager on her. She clapped her hands and said: "When I grow up, I want to be just like you!"